Ok i have seen a lot of posts here and followed them all but it does not fix my issue. I have a 98 slk230 sport... I turn the engine and the lights turn on, but the starter dosnt engage... I was told it was one of five things...

One: battery, battery tested good and no bad cells

Two: battery power relay, replaced with brand new

Three: starter, replaced starter with new one... During the test to see if this was the final step the starter made two rotations to try and engage the engine but then stopped... Ever since then we are back at step one...

Four: the k40 board... No burnt fuses and board looks brand new

Five: crank position sensor, replaced and same issues.....

I am now at a loss as to what the problem could be... All electronics work, but no engine.. I could use some assistance with this

Try putting some cables on the battery to jump it, if it starts its the battery. One problem I had years ago was the K40, all looked good but investigating further with a magnifying glass I found several solder joints cracked.

I am not sure if yours is exactly the same as my 2002, but there is a control module for the starter in the engine bay fuse box. If you remove the cover surrounding the fuses, you will see it. The light purple wire with a white stripe is what you want to look for. Have someone stick it with a test light when you turn the key to start the car. If your test light illuminates, then you know it is trying to run the starter. This should at the very least help you isolate the issue. I would also check each and every fuse...doesn't hurt when you are stumped.

First please update your location and vehicle (year?: 1996-2016, model?: 32, 200, 230, 250, 280, 300,320,350,55) in your profile as it helps the members answer your questions which usually are based on that information if you haven’t.
Follow exactly to update: ‘Usercp’ at the top of page, then ‘edit your details’ on the left side, ‘additional information’ near the bottom, edit your ‘location’ and ‘vehicle’. Info in your garage does not update your profile.

Some tips to make your visit here more enjoyable:
If you haven’t, please use the 'search' feature at the top right of the page for your questions as they have probably been asked before. Remember, ‘Search’ is your friend.
If you wish to become PM (Private Message) capable, you need 15 posts. To get those 15 posts quickly, just go to the ‘New members introduce yourself here’ section and welcome enough new members to obtain your needed posts to PM.
Want to post a picture? Start a new thread or make a post, click ‘edit’, click on the ‘paper clip’ or ‘advanced’ and/or ‘manage attachments’ then ‘choose file’ then ‘upload’ and ‘submit’! If Iphone pics, you need to rename any additional pics as Iphone names its pics all the same, image.jpg.
Want to ‘like’ or thank’ someone’s comments? Use the ‘like’ button to the right or the ‘Thanks’ button, bottom right of any post you like. This saves you having to comment.
New members should be aware that the 'New Posts' link next to the 'Search' link top right of the info bar is a great way to see all of the posts you have missed since you were on the forum last. Remember to click 'mark forums read' under ‘quick links’ when you leave.
Post your vin in the Vehicle Datacard Request section to get a free datacard (options on your car). You must update your profile with vehicle info and your location and post an introduction first.
Also vote or enter our Ride of the Month competition: ROTM Submissions & Voting - Mercedes Benz SLK Forum

Thank you
Jeff
Moderator/Founding Member/Ride of the Month Coordinator

You must
have an iframe-compatable browser to view the ImageShack.us upload form.

Register Now

In order to be able to post messages on the Mercedes Benz SLK Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:

Password

Please enter a password for your user account. Note that passwords are case-sensitive.